In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average ...In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average of the stochastic solution in the case of small population size. The choice of this model takes into account the random fluctuations inherent to the epidemiological characteristics of rural populations of Niger, notably a high prevalence of measles in children under 5, coupled with a very low immunization coverage.展开更多
In this paper, we analyze the quasi-stationary distribution of the stochastic <em>SVIR</em> (Susceptible, Vaccinated, Infected, Recovered) model for the measles. The quasi-stationary distributions, as disc...In this paper, we analyze the quasi-stationary distribution of the stochastic <em>SVIR</em> (Susceptible, Vaccinated, Infected, Recovered) model for the measles. The quasi-stationary distributions, as discussed by Danoch and Seneta, have been used in biology to describe the steady state behaviour of population models which exhibit discernible stationarity before to become extinct. The stochastic <em>SVIR</em> model is a stochastic <em>SIR</em> (Susceptible, Infected, Recovered) model with vaccination and recruitment where the disease-free equilibrium is reached, regardless of the magnitude of the basic reproduction number. But the mean time until the absorption (the disease-free) can be very long. If we assume the effective reproduction number <em>R</em><em><sub>p</sub></em> < 1 or <img src="Edit_67da0b97-83f9-42ef-8a00-a13da2d59963.bmp" alt="" />, the quasi-stationary distribution can be closely approximated by geometric distribution. <em>β</em> and <em>δ</em> stands respectively, for the disease transmission coefficient and the natural rate.展开更多
文摘In this article, we consider the construction of a SVIR (Susceptible, Vaccinated, Infected, Recovered) stochastic compartmental model of measles. We prove that the deterministic solution is asymptotically the average of the stochastic solution in the case of small population size. The choice of this model takes into account the random fluctuations inherent to the epidemiological characteristics of rural populations of Niger, notably a high prevalence of measles in children under 5, coupled with a very low immunization coverage.
文摘In this paper, we analyze the quasi-stationary distribution of the stochastic <em>SVIR</em> (Susceptible, Vaccinated, Infected, Recovered) model for the measles. The quasi-stationary distributions, as discussed by Danoch and Seneta, have been used in biology to describe the steady state behaviour of population models which exhibit discernible stationarity before to become extinct. The stochastic <em>SVIR</em> model is a stochastic <em>SIR</em> (Susceptible, Infected, Recovered) model with vaccination and recruitment where the disease-free equilibrium is reached, regardless of the magnitude of the basic reproduction number. But the mean time until the absorption (the disease-free) can be very long. If we assume the effective reproduction number <em>R</em><em><sub>p</sub></em> < 1 or <img src="Edit_67da0b97-83f9-42ef-8a00-a13da2d59963.bmp" alt="" />, the quasi-stationary distribution can be closely approximated by geometric distribution. <em>β</em> and <em>δ</em> stands respectively, for the disease transmission coefficient and the natural rate.